Dissension rhymes with:
ascension, condescension, apprehension, ascension, attention, comprehension, condescension, contention, convention, detention, dimension, extension, gentian, henschen, hypertension, hypotension, invention, laurentian, mention, misapprehension, pension, pretension, prevention, reinvention, retention, suspension, tension
Dissension sounds like:
decommission, deconcini, deukmejian, dickensian, dickenson, dickinson